A Manhattan beautician was savagely stabbed and killed in a Garment District salon this afternooon — attacked by her crazed husband who left her in a pool of blood before snatching her wallet and grabbing cash from the register, police sources and stunned witnesses told The Post.

“He looked at me with crazy eyes,” said Leo Pinkhasov, 51, owner of D’Galina’s Center Salon on West 35th Street between Sixth and Seventh avenues.

The butcher came to the salon earlier today with the well-liked Denise Kenny, 41, of Queens, Pinkhasov said.

He said the good-hearted Kenny, a native of Trinidad, had confessed to him just two days ago that she desperately wanted to break up with husband Michael Kenny, 42 — but that he adamantly refused.

Sometime after 1:30 p.m., the Kennys went upstairs from the ground-floor salon to talk, Pinkhasov and two other men inside the salon said. Pinkhasov said he heard arguing, and then saw Michael Kenny come downstairs, grab his wife’s wallet and storm back up to the second floor.

Then around 3:30 p.m., there was a blood-curdling scream, the witnesses said.

Michael Kenney then reappeared downstairs — with blood all over his shoes, tracking it across the floor, and leaving a smear on the hallway wall.

He then dashed to the cash register and grabbed the money inside and left as the stunned owner, partner Eddie Khai, 42, and stylist Joe Baiada stared in disbelief and fear.

Pinkhasov said he ran upstairs and found his worker slumped over the toilet in a bathroom.

“The blood was all over the place,” Pinkhasov said, “I pulled her down and said ‘Denise! Denise!’…” She was struggling to breathe, he said.

The woman was rushed to Bellevue, where she was pronounced dead. Police said she’d been slashed at around 3:30 p.m.

Baiada, 68, said he thought the couple were fighting — but never imagined such carnage.

“I thought maybe he punched her,” he said after the stylist began to scream.

But when the attacker came downstairs with blood all over his shoes, “I thought she must have been bleeding.”

Police sources said Kenny and her husband had previously argued in front of workers at the salon.

“She was just really nice,” said Ryan Colby, 38, head of his own modeling agency who often sent male models to Kenny.

“She was the only one I let touch the boys’ hair. She was never not there — she seemed to work there five days a week,” he said.

But Colby said he never suspected she had a troubled relationship.

“She never mentioned anything — we always just talked about the boys,” he said. “It’s very sad — I walk by here every morning. She’s one of three people I say ‘hi’ to in the morning.”